<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="./jQuerymini.js"></script>
    <style>
        * {
            padding: 0;
            margin: 0;
            list-style: none;
        }

        .main {
            display: flex;
            width: 200px
        }

        .main li {
            flex: 1;
        }

        .main a {
            text-decoration: none;

        }

        .main li ul {
            display: none;
        }
    </style>
</head>

<body>
    <ul class="main">
        <li>
            <a href="">微博</a>
            <ul class="l1">
                <li>11</li>
                <li>22</li>
                <li>33</li>
            </ul>
        </li>
        <li>
            <a href="">私信</a>
            <ul class="l2">
                <li>11</li>
                <li>22</li>
                <li>33</li>
            </ul>
        </li>
        <li>
            <a href="">评论</a>
            <ul class="l3">
                <li>11</li>
                <li>22</li>
                <li>33</li>
            </ul>
        </li>
        <li>
            <a href="">@我</a>
            <ul class="l4">
                <li>11</li>
                <li>22</li>
                <li>33</li>
            </ul>
        </li>
    </ul>
    <script>
        $(function () {
            $('.main>li').mouseover(function () {
                $(this).children('ul').show();
            })
            $('.main>li').mouseleave(function () {
                $(this).children('ul').hide();
            })
        })
    </script>
</body>

</html>